TVA vulnerable to cyberattack

A government report warns that the massive Tennessee Valley Authority may be vulnerable to a crippling attack by computer hackers, CNN said Wednesday.

The network said it had seen an advance copy of the Government Accountability Office (GAO) report prior to its release.

The GAO said the massive electric power-producer "has not fully implemented appropriate security practices to protect the control systems used to operate its critical infrastructures."

The TVA supplies electricity to about 9 million people, but is potentially vulnerable to a huge blackout engineered by a skilled hacker, CNN said.